How to estimate the standard deviation of canny edge detection

I want to segment a video using canny edge detection. I want to know if there is a method to estimate the standard deviation automatically used in canny algorithm?

[Sean de Wolski]

What do you mean the standard deviation automatically?

[ray li]

For different image, canny algorithm will use different sigma to smooth images and get good result of segmentation. If there are some methods to estimate sigma using the image information，no need to set the parameters manually.

Answer 1

[Sean de Wolski]

Do you want something like stdfilt?

doc stdfilt

[Image Analyst]

Or maybe something like std(yourImageArray(:))??? This question definitely needs more explanation.

Answer 2

[ray li]

Now, I estimate the noise variance to replace the sigma in canny algorithm. Thanks everyone.